Movable marking system, controlling method for movable marking apparatus, and computer readable recording medium

ABSTRACT

Provided are a movable marking system, a method of controlling a movable marking apparatus, and a computer-readable recording medium. The movable marking system is a movable marking system that includes a movable marking apparatus, and includes: a data receiving unit for receiving marking data regarding a working surface; a marking unit for performing a marking operation on the working surface in response to the marking data; a sensing unit for scanning space targeted for scanning; a scan condition setting unit for setting a movement path of the movable marking apparatus corresponding to the marking data, setting a scan position for scanning the space targeted for scanning by taking into account reference map data corresponding to the space targeted for scanning, and setting a scan angle of the sensing unit at the scan position; and a position detecting unit for detecting a position of the movable marking apparatus by comparing scan data obtained through the sensing unit at the scan position with the reference map data.

CROSS-REFERENCE TO RELATED APPLICATIONS

The instant application is a continuation application of U.S.application Ser. No. 16/100,815 filed on Aug. 10, 2018, which is acontinuation of PCT international application No. PCT/KR2018/005669filed on May 17, 2018, and claims priority to Korean patent applicationNo. 10-2017-0062392 filed on May 19, 2017, the entire disclosures ofwhich are hereby incorporated by reference.

TECHNICAL FIELD

The disclosure relates to a movable marking system, a controlling methodfor a movable marking apparatus, and a computer-readable recordingmedium, and more particularly, to a movable marking system capable ofcorrecting its position in space on its own by using a laser scansignal, a controlling method for a movable marking apparatus, and acomputer-readable recording medium.

BACKGROUND ART

Limits and/or problems between drawings and actual analysis thereofoccur not only in construction sites of building and/or engineering workbut also in a case of marking particular content on a working surface.That is, in order to mark particular content, such as an advertisement,on the working surface, a worker has to see a original drawing andmanually mark it on the working surface, meaning that every work dependson the proficiency of the worker. In this case, accuracy deteriorates,and if the same content is repeatedly marked, the problem worsens. Suchthe problem may occur not only in the construction field but also inother fields, such as heavy industry, city planning, and the like, whichrequire marking according to position measurement.

In addition, when work is done by using a machine/robot, the workingmachine/robot is required to have a function of identifying its accurateposition on its own.

DESCRIPTION OF EMBODIMENTS Technical Problem

Provided is a movable marking system capable of determining anenvironment of space targeted for scanning or space targeted for workand accurately determining its position, a method of controlling amovable marking apparatus, and a computer-readable recording medium.

Solution to Problem

According to an aspect of the disclosure, a movable marking systemincluding a movable marking apparatus includes: a data receiving unitfor receiving information regarding space targeted for scanning; adriver for providing power to the movable marking apparatus; a sensingunit for scanning the space targeted for scanning; a scan conditionsetting unit for setting a movement path of the movable markingapparatus, setting a scan position for scanning the space targeted forscanning by taking into account reference map data corresponding to thespace targeted for scanning, and setting a scan angle of the sensingunit at the scan position; and a position detecting unit for detecting aposition of the movable marking apparatus by comparing scan dataobtained through the sensing unit at the scan position with thereference map data.

The movable marking system may further include a map generating unit forgenerating the reference map data from scan data obtained through thesensing unit at a reference position.

The reference map data may be generated from a drawing corresponding tothe space targeted for scanning.

The movable marking system may further include a position correctingunit for correcting the position of the movable marking apparatus bycomparing the position of the movable marking apparatus detected in theposition detecting unit with the movement path.

When the position of the movable marking apparatus is off the movementpath by a predetermined range or more, the position correcting unit maycorrect the position of the movable marking apparatus so as tocorrespond to the movement path.

The movable marking system may further include a control unit forcontrolling the movable marking apparatus and a position of a markingunit, wherein, when the position of the movable marking apparatusdetected in the position detecting unit is off the movement path by apredetermined range or more, the control unit may adjust the position ofthe movable marking apparatus in response to the movement path, and whenthe position of the movable marking apparatus is off the movement pathby less than the predetermined range, the control unit may adjust theposition of the marking unit in response to the movement path.

The scan position may be on the movement path.

The movable marking system may further include a marking unit forperforming a marking operation corresponding to marking data regarding aworking surface, wherein the movement path of the movable markingapparatus may be set in response to the marking data.

The position detecting unit may receive a position signal from atransceiver in an arbitrary position and may determine the position ofthe movable marking apparatus from the position signal.

The position detecting unit may determine the position of the markingunit by comparing the marking data with data corresponding to anoperation result of the marking unit, and may determine the position ofthe movable marking apparatus by taking into account a distance betweenthe movable marking apparatus and the marking unit.

According to another aspect of the disclosure, a movable marking systemincluding a movable marking apparatus includes: a data receiving unitfor receiving information regarding space targeted for scanning; adriver for providing power to the movable marking apparatus; a sensingunit for scanning the space targeted for scanning; and a positiondetecting unit for detecting a position of the movable marking apparatusby comparing reference map data corresponding to the space targeted forscanning with scan data obtained in the sensing unit.

The position detecting unit may extract some scan data from the entirescan data obtained through the sensing unit and compare the some scandata with the reference map data, wherein the some scan data may beextracted by taking into account an amount of information regarding thespace targeted for scanning at a position where the corresponding scandata was obtained.

The position detecting unit may determine a scan position and a scanangle range at the scan position by taking into account an amount ofinformation obtainable with respect to the space targeted for scanning,and may extract scan data corresponding to the determined scan positionand scan angle and compare the scan data with the reference map data.

According to another aspect of the disclosure, a method of controlling amovable marking apparatus including a rotatable scanning sensor and adriving apparatus includes: receiving information regarding spacetargeted for scanning; setting a movement path of the movable markingapparatus; setting a scan position for scanning the space targeted forscanning by taking into account characteristics of an object in thespace targeted for scanning, which are obtained from reference map datacorresponding to the space targeted for scanning, and setting a scanangle of the scanning sensor at the scan position; and determining aposition of the movable marking apparatus by comparing scan dataobtained through the scanning sensor at the scan position with thereference map data.

The method may further include comparing the position of the movablemarking apparatus with the movement path and correcting the position ofthe movable marking apparatus, wherein the correcting of the position ofthe movable marking apparatus may include correcting, when the positionof the movable marking apparatus determined in the determining of theposition is off the movement path by a predetermined range or more, theposition of the movable marking apparatus so as to correspond to themovement path.

The receiving of the information regarding the space targeted forscanning may include receiving marking data regarding a working surfaceincluded in the space targeted for scanning, and the setting of themovement path may include setting the movement path of the movablemarking apparatus in response to the marking data.

The method may further include: obtaining scan data of the spacetargeted for scanning by rotating the scanning sensor at a referenceposition; and generating the reference map data of the space targetedfor scanning from the scan data.

The reference map data may be generated from a drawing corresponding tothe space targeted for scanning.

The scan position may be on the movement path.

Meanwhile, a computer-readable recording medium having recorded thereona program for performing a method of controlling a movable markingapparatus according to the disclosure may be provided.

Advantageous Effects of Disclosure

The disclosure may provide a movable marking system capable ofdetermining an environment of space targeted for scanning or spacetargeted for work and accurately determining its position, a method ofcontrolling a movable marking apparatus, and a computer-readablerecording medium.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 schematically illustrates configurations of a movable markingsystem according to an embodiment of the disclosure.

FIG. 2 illustrates an example of a process of setting a scan positionand a scan angle.

FIG. 3 illustrates an example of a data conversion process in whichreference map data is compared with scan data to determine a position ofa movable marking apparatus.

FIG. 4 schematically illustrates configurations of a sensing unitaccording to another embodiment of the disclosure.

FIG. 5 illustrates an example of a data obtaining cycle through ascanning sensor, an inertial measurement unit (IMU), and an encoder.

FIGS. 6A and 6B illustrate an example of a process of performing markingwork by comparing a prior map with scan data.

FIGS. 7A and 7B schematically illustrate a method of determining amoving path and a marking path of a movable marking apparatus.

FIGS. 8A-8C illustrate an example of a correcting method of markingdata.

FIG. 9 schematically illustrates configurations of a movable markingsystem according to another embodiment of the disclosure.

FIG. 10 schematically illustrates configurations of a movable markingsystem according to another embodiment of the disclosure.

FIG. 11 illustrates an example of an operation in which a movablemarking system corrects a position on space, according to thedisclosure.

FIG. 12 schematically illustrates configurations of a marking unitaccording to an embodiment of the disclosure.

FIG. 13 schematically illustrates configurations of a marking moduleaccording to another embodiment of the disclosure.

FIG. 14 illustrates an example of a plan view of a movable markingapparatus, according to an embodiment of the disclosure.

FIG. 15 illustrates an example of a moving path of a movable markingapparatus, according to an embodiment of the disclosure.

FIG. 16 illustrates an example of a reference map obtained through amovable marking apparatus, according to another embodiment of thedisclosure.

FIG. 17 is a flowchart schematically illustrating a flow of a method ofcontrolling a movable marking apparatus, according to an embodiment ofthe disclosure.

FIG. 18 is a flowchart schematically illustrating a flow of a method ofcontrolling a movable marking apparatus, according to another embodimentof the disclosure.

FIG. 19 schematically illustrates configurations of a movable markingsystem according to another embodiment of the disclosure.

FIG. 20 schematically illustrates configurations of a sensing unitaccording to another embodiment of the disclosure.

FIGS. 21A and 21B illustrate an example of a method of using a referenceposition, according to another embodiment of the disclosure.

MODE OF DISCLOSURE

Advantages and features of the disclosure and methods of accomplishingthe same may be understood more readily by reference to the followingdetailed description of embodiments and the accompanying drawings.However, the disclosure may be embodied in many different forms andshould not be construed as being limited to the embodiments set forthherein, and it is to be appreciated that all changes, equivalents, andsubstitutes that do not depart from the spirit and technical scope ofthe disclosure are encompassed in the disclosure. The embodiments setforth herein are provided so that this disclosure may be thorough andcomplete and may fully convey the scope of the disclosure to one ofordinary skill in the art. In the description of the disclosure, certaindetailed explanations of the related art are omitted when it is deemedthat they may unnecessarily obscure the essence of the disclosure.

The terms used herein are merely used to describe embodiments and arenot intended to limit the disclosure. An expression used in the singularencompasses the expression of the plural, unless it has a clearlydifferent meaning in the context. In the present specification, it is tobe understood that the terms such as “include” and “comprise” areintended to indicate the existence of features, numbers, steps, actions,components, parts, or combinations thereof described in thespecification and are not intended to preclude the possibility that oneor more other features, numbers, steps, actions, components, parts, orcombinations thereof may exist or may be added. While such terms as“first” and “second” may be used to describe various components, suchcomponents must not be limited to the above terms. The above terms areused only to distinguish one component from another.

Referring to FIG. 1, a movable marking system 100 according to anembodiment of the disclosure may include a movable marking apparatus 10,and taken as a whole, may include a data receiving unit 110, a drivingunit 120, a sensing unit 130, a scan condition setting unit 140, and aposition detecting unit 150.

The data receiving unit 110 receives information regarding spacetargeted for scanning. In the present specification, the space targetedfor scanning may refer to space targeted for work, which is a space thatthe movable marking apparatus 10 works on, and the information receivedby the data receiving unit 110 may include a drawing corresponding tothe space targeted for work, information regarding positions and sizesof a wall, a pillar, a window, etc. in the space targeted for work, thatis, information regarding architectural and spatial elements of thespace targeted for work. In addition, the data receiving unit 110 mayreceive information regarding a task that the movable marking apparatus10 has to perform in the space targeted for work.

The information regarding the space targeted for scanning may includeinformation regarding an allowable movement range of the movable markingapparatus 10. For example, the space targeted for scanning may includespace where a wall, a pillar, a window, etc. have to be installed, andthere may be space where the movable marking apparatus 10 has to beprevented from entering until they are installed. In space where a wallhas to be built or an elevator has to be installed, a floor surface maybe discontinuous, and in some cases, the movable marking apparatus 10may be in danger of falling.

Accordingly, the information regarding the space targeted for scanningmay include information regarding the allowable movement range, andthus, a moving range of the movable marking apparatus 10 may be limited.

The data receiving unit 110 may be connected to the sensing unit 130 ina wired or wireless manner and thus may receive data obtained from thesensing unit 130. Selectively, the data receiving unit 110 may include aterminal to which an external storage medium such as a universal serialbus (USB) port, a compact disc read-only memory (CD-ROM), etc. may beconnected and thus may receive data regarding the space targeted forscanning stored in the external storage medium. Selectively, the datareceiving unit 110 may be electrically connected to a separate inputunit (not shown) and thus may receive data regarding the space targetedfor scanning input from the input unit. Selectively, the data receivingunit 110 may be electrically connected to a separate computing apparatusand thus may receive data regarding the space targeted for scanning fromthe computing apparatus.

The driving unit 120 provides power to the movable marking apparatus 10.The driving unit 120 may be in any form of assigning mobility byproviding power to the movable marking apparatus 10, and for example,the driving unit 120 may include a wheel or a caterpillar or may includea wing or a propeller. In addition, the driving unit 120 may include astructure imitating a leg of a human being or an animal, and may includea structure capable of moving and performing work even under water.

The sensing unit 130 scans the space targeted for scanning. The sensingunit 130 may include, but is not limited to, a scanning sensor and adriver such as a motor for controlling a rotating operation of thescanning sensor, and when a sensing range of the sensor is 360 degrees,the sensing unit 130 may not include a driver. In the presentspecification, terms such as “scan” and/or “scanning” may be used todescribe all cases of sensing a target space and/or object by using asensor and are not restrictively interpreted by a dictionary definition.The movable marking apparatus 10 may include the data receiving unit110, the driving unit 120, and the sensing unit 130, and the scancondition setting unit 140 and the position detecting unit 150 may bespaced from the movable marking apparatus 10 independently of themovable marking apparatus 10.

Although FIG. 1 illustrates the scan condition setting unit 140 and theposition detecting unit 150 included in a separate computing apparatus11, this is merely an embodiment, and the disclosure is not limitedthereto. Accordingly, the computing apparatus 11 may be coupled to themovable marking apparatus 10, and the scan condition setting unit 140and the position detecting unit 150 may serve as components of themovable marking apparatus 10.

Meanwhile, the scanning sensor is a sensor for measuring a distance toan object, sensing a form of an object, or sensing movement of themovable marking apparatus 10, and may include a sensor using laser orusing sound waves, light waves and/or radio waves, an inertialmeasurement unit (IMU) sensor, a global positioning system (GPS) sensorand/or may include an image acquiring sensor, such as a camera, capableof acquiring a moving image and/or a still image. When the scanningsensor includes a laser sensor, a LiDAR sensor may be included as anexample of the laser sensor. The sensing unit 130 may include at leastone sensor described above, and sensing precision may be improved bycombining different types of sensors. For example, movement of themovable marking apparatus 10 may be sensed by using a LiDAR sensor as alaser sensor and further including an IMU sensor, and thus, sensingprecision with respect to space targeted for scanning may improve. Inaddition, a camera sensor may be selectively and/or additionallyincluded to allow the camera sensor to capture an image of spacetargeted for scanning. For example, an image of a state and/or textureof a certain surface, more particularly, a floor surface of spacetargeted for scanning may be captured, and thus, a movement and/or workpath of the movable marking apparatus 10 may be set and/or corrected. Inaddition, a distance measurement sensor may be selectively and/oradditionally included, and thus, a distance to a certain point, forexample, a wall or a pillar, may be measured. Accordingly, a measuredposition of the certain point in the space targeted for scanning may bereflected to set and/or correct a movement and/or work path of themovable marking apparatus 10. Such configurations of the sensing unit130 may be applied to all embodiments of the present specification.

The movable marking apparatus 10 may scan surrounding space by using thescanning sensor, and may obtain a position of an object in thesurrounding space in the form of polar coordinates by using informationwhere a scan signal output by the scanning sensor is reflected. Themotor allows the scanning sensor to rotate by as much as a desiredangle, for example, 360°. A rotating direction of the scanning sensormay be variously controlled as necessary.

Meanwhile, horizontal rotation, horizontal movement, tilt and/orvertical movement of the scanning sensor may be controlled by a separatedriver. Horizontal rotation, horizontal movement, tilt and/or verticalmovement of the scanning sensor may be controlled independently of oneanother, and control signals for controlling the horizontal rotation,horizontal movement, tilt and/or vertical movement may also beindependently generated and be provided to the driver.

The scan condition setting unit 140 may set a movement path of themovable marking apparatus 10, may set a scan position in the spacetargeted for scanning by taking into account reference map datacorresponding to the space targeted for scanning, and may set a scanangle of the sensing unit 130 at the scan position. The scan angle mayinclude a scanning direction of the sensing unit 130. In this regard,the scan condition setting unit 140 may set a scan position and/or ascan angle by taking into account characteristics of an object in thespace targeted for scanning obtained from reference map data.

The scan condition setting unit 140 sets the movement path, anddesignates an arbitrary point on the movement path to set the designatedpoint as a scan position. According to the space targeted for scanning,if necessary, a plurality of positions may be set as the scan position.In response, when the movable marking apparatus 10 arrives at the scanposition, the scanning sensor performs a scanning operation. In thisregard, the scanning sensor rotates according to a scan angle set by thescan condition setting unit 140.

Meanwhile, a scan height of the scanning sensor may be adjusted, and thescan condition setting unit 140 may set a scan angle and a scan heightof the scanning sensor together at a set scan position. The scanposition and the scan angle may be set by taking into accountcharacteristics of the space targeted for scanning, for example,characteristics of an object in the space targeted for scanning.

The scan position and the scan angle are set by taking the reference mapdata into account, and for example, a position and an angle where apillar, a window, an obstacle, etc. in the space targeted for scanningmay be avoided may be set as the scan position and the scan angle.

In a case where it is difficult to obtain scan data, for example, in acase of transmitting light without reflection, the scan position and thescan angle may be arranged in empty space of the space targeted forscanning so that a position and an angle where a pillar, an obstacle, orthe like may be scanned may be set as the scan position and the scanangle.

When there is a drawing of the space targeted for scanning, the scancondition setting unit 140 may set the movement path, the scan positionand/or the scan angle of the scanning sensor at the scan position bytaking the drawing into account.

The movable marking apparatus 10 may be understood as performing ascanning operation at a certain position on the movement path. Thecertain scan position is designated to accurately identify a position ofthe movable marking apparatus 10.

Although a finite number of positions may be set as the certainposition, the disclosure is not limited thereto, and a scanningoperation may be continuously performed while moving on the movementpath.

Meanwhile, the scan angle refers to a scanning angle of the scanningsensor at each scan position and may be represented as degrees orradians. A size of the scan angle may be represented based on an x-axisor may be represented based on an angle of the scanning sensorcorresponding to a time when a scanning operation at the very previousscan position is finished.

In an embodiment of the disclosure, the movable marking apparatus 10 maystop at each scan position, and while stopping at the scan position, mayallow the scanning sensor to rotate and scan surrounding space.Alternatively, in another embodiment of the disclosure, the movablemarking apparatus 10 may not stop at the scan position, and whilemoving, may scan surrounding space via the scanning sensor. The positiondetecting unit 150 detects a position of the movable marking apparatus10 by comparing scan data obtained via the sensing unit 130 at theplurality of scan positions with the reference map data.

The reference map data may be represented as coordinates of a pixelincluded in an image frame, and coordinates of a pixel corresponding toa position of an object may have different values from coordinates of apixel corresponding to an empty position. As described above, dataobtained via the scanning sensor may be obtained in the form of polarcoordinates, and when the reference map data is compared with the scandata, a position of the movable marking apparatus 10 in the spacetargeted for scanning may be determined.

In detail, the position detecting unit 150 may convert the reference mapdata into data in the form of polar coordinates obtained via thescanning sensor and may compare the converted data with the scan data.

In another embodiment of the disclosure, the position detecting unit 150may receive a position signal output from a transceiver (not shown)installed at an arbitrary position and may determine a position of themovable marking apparatus 10 from the position signal. When a positionof the transceiver is determined, the transceiver may determine aposition of the movable marking apparatus 10 based on the position ofthe transceiver and may provide determined position information to theposition detecting unit 150. The transceiver may be installed indoorsand may communicate with the movable marking apparatus 10, therebyhelping determination of a position of the movable marking apparatus 10.As another example, the transceiver may be installed, for example, atfour corners of a building and may recognize a coordinate value of thebuilding by receiving a GPS signal and then transmit a new signal basedon the value, thereby helping determination of a position of the movablemarking apparatus 10. Alternatively, the position detecting unit 150 maydetermine a position of the movable marking apparatus 10 by taking intoaccount a distance from the movable marking apparatus 10 to thetransceiver, angle data, and position information of the transceiver.Selectively, the position detecting unit 150 may sense a position of amarker (not shown) installed at an arbitrary position and may determinea position of the movable marking apparatus 10 from the marker. Forexample, the position detecting unit 150 may determine a position of themovable marking apparatus 10 inversely from a position where a positionof the marker is sensed and/or analysis of sensed data.

An operation performed by the position detecting unit 150 intends todetermine a position of the movable marking apparatus 10 as accuratelyas possible, and the transceiver and/or the marker may be attached on anarbitrary position, for example, a pillar or a wall of the spacetargeted for scanning, to transmit the position signal and/or mark aposition.

However, a location of the transceiver and/or the marker is not limitedto an arbitrary position inside the space targeted for scanning. Forexample, when the space targeted for scanning is open space, a positionof the movable marking apparatus 10 may be traced even if thetransceiver and/or the marker is outside the space targeted forscanning.

The movable marking apparatus 10 may include a receiver (not shown)capable of receiving the position signal and determining a position ofthe transceiver transmitting the received position signal and a distanceand/or an angle with respect to the transceiver, and the receiver maydetermine a position of the movable marking apparatus 10 by taking intoaccount a position signal received from at least one transceiver.

The transceiver may be configured through a signal sharer or a beaconand may be used when an accurate position of the movable markingapparatus 10 is difficult to determine through comparison between thescan data and the reference map data.

The marker may mark a certain color or shape or a predetermined number,and a receiver of the movable marking apparatus 10 may determine aposition of the movable marking apparatus 10 by recognizing the color,the shape, or the number. The marker may be displayed so as to beidentifiable through a special apparatus such as an ultraviolet camera.

FIG. 2 is a diagram illustrating an example of a process of setting ascan position and a scan angle.

The scan condition setting unit 140 may set a scan angle at each scanposition by taking into account an amount of the scan data obtainedaccording to a scan angle of the scanning sensor on a movement path ofthe movable marking apparatus 10 in space S targeted for scanning. As anamount of the scan data obtained increases, accurate informationregarding the space S targeted for scanning may be obtained. This may beunderstood as setting a scan position and/or a scan angle by taking intoaccount characteristics of an object in space targeted for scanningobtained from reference map data corresponding to the space targeted forscanning.

When the scan position and the scan angle change within the spacetargeted for scanning, an amount of the scan data obtained via thescanning sensor may change. For example, referring to FIG. 2, positionA, position B, and position C are examples of a scan position on amovement path of the movable marking apparatus 10, and at position A, itmay be expected to obtain the largest amount of scan data when a scanangle of the scanning sensor is set in a northeast direction. It may beunderstood that this is because of limiting a sensing range of thescanning sensor to a certain angle, and in an embodiment, the sensingrange of the scanning sensor may be 180°. However, the sensing range ofthe scanning sensor is not limited to 180°.

At position B, it may be determined that a relatively similar amount ofscan data may be obtained even though the scan angle is set in anydirection, and at position C, it may be expected to obtain the largestamount of scan data when the scan angle is set in a northwest direction.

The scan condition setting unit 140 may set a scan angle at which thescan data is expected to be obtained most, and as described above, thescan angle may be set differently at each scan position.

The scan condition setting unit 140 may use the reference map data toset the scan angle and the scan position, and to set a scan angle ateach scan position, may simulate an amount of the scan data obtainedwith respect to various sensing angles by taking into account a sensingrange of the scanning sensor at the scan position.

The scan condition setting unit 140 may take a speed of the movablemarking apparatus 10 into account to determine the scan position. Thescanning sensor continuously performing a scanning operation may obtainmore accurate scan data at a section where the movable marking apparatus10 moves slowly. On the other hand, accuracy of scan data obtained at asection where the movable marking apparatus 10 moves quickly may berelatively low.

Although simulation of an amount of the scan data obtained may beperformed at every position on the movement path of the movable markingapparatus 10, work speed may decrease when a computational amountincreases, and thus, some positions may be set as the scan position.

Accordingly, the scan condition setting unit 140 may set a scan angle ofthe scanning sensor corresponding to a point where a speed of themovable marking apparatus 10 is equal to or greater than a predeterminedvalue.

A moving speed of the movable marking apparatus 10 at a straight sectionmay be greater than that at a curved section. Since the moving speed ofthe movable marking apparatus 10 may be predetermined in response to amovement path of the movable marking apparatus 10, the scan conditionsetting unit 140 may set the scan position by taking the movement pathinto account.

In FIG. 2, when a speed of the movable marking apparatus 10 at positionsA, B, and C is equal to or greater than a predetermined value, positionsA, B, and C may be set as scan positions. In addition, when a scan angleat position A is 45° (northeast direction), and a scan angle at positionB is 270° (south direction), the movable marking apparatus 10 may movefrom position A to position B along a determined movement path, and inresponse, a scan angle of the scanning sensor may continuously changefrom 45° to 270°. In this regard, a change direction of the scan angle,that is, a rotation direction of the scanning sensor, is not limited toany one of a clockwise direction and a counterclockwise direction andmay be determined as a direction where the largest amount of scan datamay be obtained by taking into account a distance between position A andposition B and a movement speed of the movable marking apparatus 10.

FIG. 3 is a drawing illustrating an example of a data conversion processin which reference map data is compared with scan data to determine aposition of a movable marking apparatus.

Referring to FIG. 3, the reference map data may be represented in a gridformat, and portions darker than other gird areas denote presence of anobject reflecting a scan signal of a laser sensor. Each grid area may berepresented as coordinates such as (x_(m,i), y_(m,i)) and (x_(m,l),y_(m,l)).

The position detecting unit 150 according to an embodiment, which isdescribed above with reference to FIG. 1, performs an operation ofcomparing the reference map data with scan data to determine a positionof the movable marking apparatus 10, and unlike the reference map dataincluding grid data, the scan data includes data regarding a distanceand an angle with respect to an object. Accordingly, the positiondetecting unit 150 may convert the reference map data in a grid formatinto data regarding a distance and an angle to compare the reference mapdata with the scan data.

Referring to FIG. 3, a position represented as coordinates of (x_(m,i),y_(m,i)) and (x_(m,l), y_(m,l)) in the reference map data may beconverted into polar coordinate data of (Φ_(m,i), d_(m,i)) and (Φ_(m,l),d_(m,i)), respectively, and the polar coordinate data matches a dataformat of the scan data. Accordingly, the position detecting unit 150may directly compare the converted reference map data with the scan dataand may determine a position of the movable marking apparatus 10 byusing a result of the comparison.

However, the reference map data and the scan data are not limited to agrid format and a polar coordinate format, respectively, and thedisclosure is not limited to converting data in the grid format into thepolar coordinate format to compare two types of data. Accordingly, thereference map data and the scan data may be represented as data of othertypes instead of the grid format and the polar coordinate format, and itis also possible to compare two types of data by converting the scandata so as to correspond to a format of the reference map data.

In FIG. 3, although a plurality of grid areas may be understood ascorresponding to respective pixels when represented through a displayapparatus, the disclosure is not limited thereto, and one grid area maycorrespond to a plurality of pixel groups. A reference point for polarcoordinate conversion is not limited to the origin (0) illustrated inFIG. 3.

When the sensing unit 130 obtains scan data regarding an object in thespace targeted for scanning, the position detecting unit 150 maydetermine the presence of matching data by comparing distance/angle datacorresponding to the scan data with the converted reference map data.

There may be various pieces of matching data depending on a result ofthe determination, and the position detecting unit 150 may improveaccuracy of position determination regarding the movable markingapparatus 10 by comparing a plurality of pieces of scan data with theconverted reference map data.

The position detecting unit 150 may determine the most reliable positionas a position of the movable marking apparatus 10 by comparing each ofthe plurality of pieces of scan data with the reference map data.

For example, when first scan data to n-th scan data are obtained byusing the scanning sensor at the same position, the position detectingunit 150 may search for reference map data corresponding to the firstpiece of scan data. As a search result, there may be m pieces ofreference map data corresponding to the first scan data, and theposition detecting unit 150 may compare the second scan data with the mpieces of reference map data. After such a process is repeatedlyperformed, a position where the first scan data to n-th scan data areobtained, that is, a position of the movable marking apparatus 10, maybe ultimately detected.

To detect a position of the movable marking apparatus 10 by comparingreference map data with scan data, the position detecting unit 150 mayuse most recently obtained scan data.

In FIG. 3, positions a, b, and c are examples of some positions on amovement path of the movable marking apparatus 10, and description isgiven below assuming that the movable marking apparatus 10 moves fromposition a to position c and the scanning sensor faces a direction fromposition a toward position c.

The scanning sensor may obtain scan data by performing a scanningoperation at positions a, b, and c, and when the scanning sensor mayscan only a limited range, for example, when the scanning sensor mayscan a total range of 180° with ±90° with respect to the front,referring to FIG. 3, data amounts of scan data obtained through thescanning sensor at respective positions a, b, and c may be differentfrom one another.

For example, an amount of scan data obtained at position a may begreater than an amount of scan data obtained at position c. In thisregard, to detect a position of the movable marking apparatus 10 bycomparing reference map data with scan data when the movable markingapparatus 10 is at position c, the position detecting unit 150 maycompare scan data obtained at position b with the reference map data.

Since an amount of scan data obtained at position a is more than that ofscan data obtained at position b, computational speed may be increasedby comparing the scan data obtained at position b with the reference mapdata.

Since the scanning sensor may obtain scan data by continuouslyperforming scanning, and the position detecting unit 150 maycontinuously detect an accurate position of the movable markingapparatus 10 by using the scanning data, using data obtained at a timeclosest to a current time may be a way of improving accuracy of positiondetection.

FIG. 4 is a drawing schematically illustrating configurations of thesensing unit 130 according to another embodiment.

Referring to FIG. 4, the sensing unit 130 according to anotherembodiment may include a scanning sensor 131, a sensor driver 132, asecond sensor 133, and a third sensor 134. As described above withreference to FIG. 1, the scanning sensor 131 is a sensor for measuring adistance to an object or scanning a form of the object, and may includea sensor using laser or using sound waves, light waves and/or radiowaves, an IMU sensor, a GPS sensor and/or an image acquiring sensor,such as a camera, capable of acquiring a moving image and/or a stillimage. The sensor driver 132 may physically control an operation of thescanning sensor 131 and may control rotary driving, tilt driving, and/orup-and-down driving of the scanning sensor 131.

In an embodiment, the sensor driver 132 may include a horizontalrotation driver (not shown), a tilt driver (not shown), a horizontaldriver (not shown) and/or a vertical driver (not shown) for controllingrotary driving, tilt driving, horizontal driving and/or vertical drivingof the scanning sensor 131. The horizontal rotation driver may control ahorizontal rotation operation of the scanning sensor 131, and the tiltdriver may control an up-and-down scan angle of the scanning sensor 131.The horizontal driver may control the scanning sensor 131 tohorizontally drive the scanning sensor 131. The vertical driver maycontrol the scanning sensor 131 to adjust height thereof by verticallydriving the scanning sensor 131.

The horizontal rotation driver, the tilt driver, the horizontal driverand/or the vertical driver may be driven independently of one another,and an operation of one driver does not limit or subordinate anoperation of another driver. Accordingly, the horizontal rotationdriver, the tilt driver, the horizontal driver and/or the verticaldriver may respectively operate according to different control signalsand may be understood as being also physically independently driven.

Up-and-down scanning may be performed on an object in the space targetedfor scanning by controlling an up-and-down scan angle of the scanningsensor 131. Although the up-and-down scan operation may be performed bythe tilt driver and/or the vertical driver, the disclosure is notlimited thereto, and a plurality of scanning sensors may be arranged atdifferent angles from each other with respect to a working surface toperform up-and-down scanning.

The second sensor 133 and the third sensor 134 may also be sensors formeasuring a distance to an object or scanning a form of the object.According to an embodiment, as sensors for measuring data of a differenttype from the scanning sensor 131, the second sensor 133 and the thirdsensor 134 may measure data which is used with the scan data obtained bythe scanning sensor 131 to determine a position of the movable markingapparatus 10.

In an embodiment, the second sensor 133 may include an IMU, and thethird sensor 134 may include an encoder.

The IMU may measure acceleration and angular speed data of the movablemarking apparatus 10, and the acceleration and angular speed data may beused to calculate a speed and an orientation angle of the movablemarking apparatus 10. The encoder is a position sensor capable ofmeasuring displacement of the movable marking apparatus 10 and mayprovide data regarding a movement distance of the movable markingapparatus 10.

Scan data obtained from the scanning sensor 131, angular speed andacceleration data obtained from the IMU, and displacement data obtainedfrom the encoder may be provided to the position detecting unit 150, andthe position detecting unit 150 may detect a position of the movablemarking apparatus 10 by putting together the pieces of measured data.

Accordingly, even when accuracy of some pieces of measured data is low,a position of the movable marking apparatus 10 may be accuratelydetected.

In another embodiment of the disclosure, the sensing unit 130 may notinclude at least the horizontal rotation driver of the sensor driver132. For example, as described above, when a scanning sensor capable ofrotating 360 degrees is used, the scanning sensor 131 may rotate on itsown, and thus, the sensor driver 132 for controlling a rotationoperation of the scanning sensor 131 may not be required. However, evenin this case, the tilt driver, the horizontal driver, and the verticaldriver may be included.

FIG. 5 illustrates an example of a cycle of obtaining data through ascanning sensor, an IMU, and an encoder.

As described with reference to FIGS. 4 and 5, the sensing unit 130 mayinclude the scanning sensor 131, the second sensor (for example, theIMU) 133, and the third sensor (for example, the encoder) 134, and theposition detecting unit 150 may take into account together scan dataobtained through the scanning sensor 131 and data regarding accelerationand angular speed obtained through the second sensor 133 to determine anaccurate position of the movable marking apparatus 10, and may also takeinto account distance data of the movable marking apparatus 10 obtainedthrough the third sensor 134.

In this regard, a reliability value may be assigned by taking intoaccount measurement accuracy of the scanning sensor 131, the secondsensor 133, and the third sensor 134, and scan data, IMU data(acceleration and angular speed data), and distance data having thereliability value reflected may be used.

Reliability regarding data obtained from the scanning sensor 131, theIMU 133, and the encoder 134 may be determined by taking into account anerror rate showing up in its own specifications of each measurementapparatus. Accordingly, a higher reliability value may be assigned todata provided from a measurement apparatus providing more accurate datacompared to other measurement apparatuses, and thus, a position of themovable marking apparatus 10 may be accurately detected.

The reliability value may vary according to time. For example, when themovable marking apparatus 10 is set to move at a speed of 1 m/s, adistance that the movable marking apparatus 10 moves during one secondshould be measured as 1 m. In addition, by taking into account distancedata measured during the one second through the encoder 134 and an errorrate according to specifications of the encoder 134, a reliability valueregarding the distance data may be differently applied after the onesecond.

When an error rate of the encoder 134 is assumed to be ±1%, in the aboveexample, the distance data may be expected to be within a range of 99 cmto 101 cm. Nevertheless, when the distance data is not within the rangeof 99 cm to 101 cm, a lower reliability value may be assigned to thedistance data. On the other hand, as the distance data is close to 1 m,a high reliability value may be assigned to the distance data.

Accordingly, obtaining the distance data during each second may beunderstood as updating a reliability value regarding the distance dataduring each second.

When time cycles of obtaining the scan data, the IMU data, and thedistance data are different from one another, a reliability value whichis assigned to each data based on data having the longest data obtainingcycle may be reset to a first assigned reliability value.

Referring to FIG. 5, it may be found that an obtaining cycle of thedistance data obtained through the encoder is shortest, and an obtainingcycle of the scan data obtained through the scanning sensor 131 islongest.

Accordingly, a reliability value regarding the distance data may beupdated during the shortest cycle, and a reliability value regarding thescan data may be updated during the longest cycle. As described abovewith reference to FIG. 2, at a time when the scan data having thelongest data obtaining cycle is obtained, a reliability value regardingall data may be reset to a first assigned reliability value.

That is, reliability values assigned for each data at a time ti and atime is may be understood as identical.

FIG. 6 is a drawing illustrating an example of a process of performingmarking work by comparing a prior map with scan data.

The prior map refers to a map including information regarding the spacetargeted for scanning and marking data corresponding to the spacetargeted for scanning, and in an embodiment, the prior map may be a CADdrawing. Selectively, the prior map may be understood as a reference mapincluding the marking data, and the prior map may provide informationregarding the space targeted for scanning even before scan dataregarding the space targeted for scanning is obtained by the sensingunit 130.

FIG. 6A illustrates a prior map, and the prior map may includeinformation and marking data regarding space targeted for scanning.Referring to FIG. 6A, the space targeted for scanning includes a firstspace 51 and a second space S2 divided by a wall, and the first space 51includes circular marking data and the second space S2 includestriangular marking data.

Information regarding the space targeted for scanning obtained from theprior map may be different from reality. Accordingly, selectively,before performing marking work, a movable marking apparatus according toan embodiment may generate a reference map by using a scanning sensor atat least one point of the space targeted for scanning.

Although an operation of the scanning sensor for generating thereference map is not illustrated in FIG. 1, the scanning sensor mayperform a scanning operation on the space targeted for scanning toobtain not only scan data for determining a position of the movablemarking apparatus but also information regarding the space targeted forscanning and may obtain scan data therefrom.

FIG. 6B illustrates a reference map generated at position D of the firstspace S1, and space denoted by a solid line denotes space that may beobtained through a scanning sensor at position D and space denoted by adash line denotes space that may not be obtained at position D.Accordingly, information regarding the space denoted by a dash line inFIG. 6B may be understood as being not included in scan data obtained atposition D.

When the scan data obtained at position D is compared with the priormap, pieces of information regarding the second space S2 do not match,and accordingly, it may be found that obtaining scan data at a newposition is required to obtain information regarding the second spaceS2. Selectively, the movable marking apparatus may mark a circle byperforming marking work in the first space 51 and may move to position Eand perform a scanning operation again.

The new scan data obtained at position E may include informationregarding the second space S2, and the scan condition setting unit 140may ultimately update the reference map by merging the new scan dataobtained at position E with scan data corresponding to FIG. 6B.

In another embodiment of the disclosure, the reference map may begenerated from sub scan data obtained through at least one sub scanningsensor (not shown) installed in space targeted for scanning. Dependingon characteristics of the space targeted for scanning, a plurality ofsub scanning sensors may be installed. For example, as illustrated inFIG. 6, when the entire space targeted for scanning includes the twoseparate spaces 51 and S2, two sub scanning sensors may be installed toobtain sub scan data regarding the first space 51 and the second spaceS2, respectively.

The sub scan data may be previously obtained even if a scanningoperation by the sensing unit 130 is not performed, and the datareceiving unit 110 may receive the sub scan data and generate thereference map. Accordingly, a process of generating a reference mapthrough the sensing unit 130 at an arbitrary position before performingwork in the space targeted for scanning may be omitted.

In addition, the scan condition setting unit 140 may set a scan positionand a scan angle by taking into account a reference map generated fromthe sub scan data.

As illustrated in FIG. 6, even when it is difficult to obtain scan dataregarding the entire space through one scanning operation, a referencemap regarding the entire space may be easily generated.

FIG. 7 is a drawing schematically illustrating a method of determining amovement path and a marking path of the movable marking apparatus.

The figure illustrated in FIG. 7 is an example of marking data, and themovable marking apparatus described above with reference to thepreceding drawings may move in space targeted for scanning and performwork corresponding to the marking data.

As described above with reference to FIG. 1, the scan condition settingunit 140 sets a movement path of the movable marking apparatuscorresponding to the marking data, and in an embodiment, the scancondition setting unit 140 may set a marking path capable of minimizinga movement distance of the movable marking apparatus by taking themarking data into account.

The scan condition setting unit 140 may extract at least one figure,line, etc. from the marking data received via the data receiving unit110, and by taking into account a connection relationship of the figure,line, etc., may designate a plurality of figures, lines, etc. connectedto each other as one group.

In addition, the scan condition setting unit 140 may calculate a markingpath capable of drawing fastest the figure, line, etc. designated as onegroup, and for example, may determine whether or not there is anEulerian path to calculate the marking path.

Referring to FIG. 7A, there are a triangle and a line connected theretoon the left, and there are a circle and a square connected thereto onthe right. Accordingly, the scan condition setting unit 140 may set thetriangle and the line as one group (hereinafter referred to as a firstgroup) and may set the circle and the square as another group(hereinafter referred to as a second group).

Next, the scan condition setting unit 140 may determine whether or notit is possible to draw in one stroke with respect to each group, andwhen it is possible to draw in one stroke, may calculate a marking path.All the figures illustrated in FIG. 7 are possible to draw in onestroke, and thus, as illustrated in FIG. 7B, the scan condition settingunit 140 may set a start point and an end point of the marking path withrespect to each group.

For example, for the first group, it is possible to draw in one strokewhen starting at point P1, and in this regard, an end point of the firstgroup is point P2. For the second group, point P3 is a start point, andat the same time, an end point, and thus, a movement path of the movablemarking apparatus may be set to move from point P2 to point P3 withoutmarking work.

Although FIG. 7 illustrates marking data including a figure, a line,etc. possible to draw in one stroke, it is not possible to draw allmarking data in one stroke, and thus, the scan condition setting unit140 may split the marking data into a minimum unit possible to draw inone stroke.

In addition, a path capable of minimizing a movement distance of themovable marking apparatus may be set as a movement path between piecesof marking data that are not connected to each other.

FIG. 8 is a drawing illustrating an example of a method of correctingmarking data.

FIG. 8A illustrates the space S targeted for scanning, which includesmarking data, and FIG. 8B illustrates space S′ targeted for scanning,which is corrected with scan data obtained through a scanning sensor.That is, the space S targeted for scanning illustrated in FIG. 8A may beunderstood as a prior map (for example, a CAD drawing) includinginformation regarding the space S targeted for scanning.

Referring to FIGS. 8A and 8B, the space S′ targeted for scanning, whichcorresponds to scan data obtained through the scanning sensor, may havea difference from the space S targeted for scanning, which correspondsto the prior map. The prior map includes information regarding the spacetargeted for scanning but may include information different from anactual work environment, and in this case, the prior map may becorrected/updated by using scan data obtained through the scanningsensor.

The prior map may include marking data, and referring to FIG. 8A, it maybe found that rectangular marking data is at the bottom right of thespace S targeted for scanning. In this regard, the scan conditionsetting unit 140 may correct the marking data by reflectingcorrection/update information regarding the space S targeted forscanning.

FIG. 8C illustrates marking data corrected according to scan data, andit may be found that a size of the marking data has been corrected inproportion to a size difference between the space S targeted forscanning of the prior map and the space S′ targeted for scanningcorresponding to the scan data.

In addition, the scan condition setting unit 140 may correct a positionof the marking data in response to correction of space targeted forscanning. For example, when a horizontal length of the space targetedfor scanning decreases, correction may be made to decrease a gap betweenthe marking data and a vertical wall.

In another embodiment, even though a size of the space targeted forscanning changes, prior to correction of the marking data, the scancondition setting unit 140 may inform a worker that a size of the spacetargeted for scanning has been measured differently and may allow theworker to select whether to correct a size and a position of the markingdata.

FIG. 9 is a drawing schematically illustrating configurations of amovable marking system 200 according to another embodiment.

Referring to FIG. 9, the movable marking system 200 according to anotherembodiment may include a data receiving unit 210, a driving unit 220, asensing unit 230, a marking unit 240, a map generating unit 250, a scancondition setting unit 260, a position detecting unit 270, and aposition correcting unit 280.

Although FIG. 9 illustrates the movable marking system 200 correspondingto the movable marking system 100 of FIG. 1 further including themarking unit 240, the map generating unit 250, and the positioncorrecting unit 280, the movable marking system 200 illustrated in FIG.9 may further include only one of the marking unit 240, the mapgenerating unit 250, and the position correcting unit 280.

The marking unit 240 performs a marking operation on a working surfacein response to marking data. The working surface refers to a surfacetargeted for marking existing in space targeted for scanning, and theworking surface may be included in the space targeted for scanning. Inaddition, a movable marking apparatus 20 may move on the workingsurface.

The marking unit 240 is provided to mark the content corresponding tothe marking data on the working surface, and any tool capable ofmarking, such as ink, a photosensitizer, light, or sound waves, may beused. In addition, marking may also be performed by applying physicalpressure to the working surface.

The marking data may include design data and text data, and the designdata and the text data are distinguished from each other. For example,the design data may include information regarding a figure, etc.described above with reference to FIGS. 6 to 8, and the text data may beunderstood as corresponding to explanation, annotation, etc. that may beprovided to a worker with regard to the design data.

The marking unit 240 may mark at least one of one-dimensional data andtwo-dimensional data on the working surface and may markthree-dimensional data on the space targeted for scanning including theworking surface. For example, the marking unit 240 may markthree-dimensional data in a stacked form by performing marking on themarked working surface as many times as necessary.

The map generating unit 250 may generate a reference map correspondingto the space targeted for scanning, and in detail, the map generatingunit 250 may generate the reference map from scan data obtained througha scanning sensor included in the sensing unit 230 at a referenceposition.

The reference position may be an arbitrary position in the spacetargeted for scanning, and in general, a center point of the spacetargeted for scanning may be selected as the reference position. Aposition close to a window or a position where there is an adjacentobstacle may not be suitable for the reference position. However, insome cases, the reference position may be an arbitrary position outsidethe space targeted for scanning.

At a window, a scan signal output from the scanning sensor may not beproperly reflected, and thus, there may be a problem with obtaining thescan data. When there is an obstacle nearby, it may be difficult toobtain scan data of space behind the obstacle.

In addition, in a space where there is no object reflecting a scansignal output from the scanning sensor, it may be difficult to obtainscan data, and thus, the reference position may be arranged in an emptyspace within the space targeted for scanning to set a position where apillar, an obstacle, or the like may be scanned as the referenceposition.

When it is difficult to obtain complete scan data due to an obstacle ora pillar, complete scan data may be obtained by performing firstscanning at the reference position and then performing second scanningby designating an arbitrary position behind the obstacle or the pillar.

In a state where the movable marking apparatus 20 stops at the referenceposition, the scanning sensor scans the space targeted for scanning byrotating 360 degrees and thus generates the scan data. If necessary, ascan angle of the scanning sensor included in the sensing unit 230 maybe controlled in a height direction through tilt control, etc. However,during a process of generating the scan data for generating thereference map, a position of the movable marking apparatus does notnecessarily need to be fixed to the reference position, and it is alsopossible to generate the scan data by rotating the scanning sensor whilethe movable marking apparatus moves within a predetermined referencespace.

The map generating unit 250 may generate a reference map of the spacetargeted for scanning from the scan data and may generate the referencemap by applying a SLAM algorithm to the scan data obtained at thereference position. The SLAM is an abbreviation of simultaneouslocalization and mapping and is also called concurrent mapping andlocalization (CML). The SLAM refers to an algorithm in which, when a mapis not given, and a position of a sensor at a map is unable to bedetermined, a map is generated while a surrounding environment is sensedvia the sensor, and a position of the sensor is also estimated at themap.

The reference map may include image data of pixels included in an imageframe corresponding to the scan data. For example, when the spacetargeted for scanning is represented as one frame, a pixel correspondingto a position of an object may be displayed in black, and a pixelcorresponding to an empty space may be displayed as white.

However, this is merely an embodiment of a data format that thereference map data may include, the disclosure is not limited toincluding color information regarding an individual pixel, and thereference map data may be represented in a format such as a vector, apolar coordinate, etc.

In another embodiment of the disclosure, the map generating unit 250 mayreceive a drawing corresponding to the space targeted for scanning andgenerate the reference map. The drawing may be understood as includinginformation regarding the space targeted for scanning, and in anembodiment, the drawing may be a CAD drawing. Accordingly, according toan embodiment, the drawing may play the same role as the reference map.

However, even though there is a drawing corresponding to the spacetargeted for scanning, the information regarding the space targeted forscanning shown in the drawing may not be accurate, and thus, the mapgenerating unit 250 may newly generate the reference map. In thisregard, the drawing and the reference map generated in the mapgenerating unit 250 may be used together and/or selectively.

When pieces of information regarding the space targeted for scanningincluded in the drawing and the reference map do not match, the drawingand the reference map may each be weighted, and information regardingspace targeted for scanning available in the scan condition setting unit260 may be provided.

In another embodiment, the map generating unit 250 may compare a priormap including information regarding the space targeted for scanning withscan data obtained through the scanning sensor to correct the prior map.In addition, the scan condition setting unit 260 may use the correctedprior map as the reference map.

For example, the prior map may be a drawing corresponding to the spacetargeted for scanning as described above, and may include marking datawithin the space targeted for scanning.

Information represented through the prior map may not matchcharacteristics of the space targeted for scanning, and in this case,the scan data obtained through the scanning sensor may provide moreaccurate information regarding the space targeted for scanning.

However, when a result of comparing the prior map with the scan data isbeyond a preset error range, the map generating unit 250 may output analarm. The alarm may be understood as a type of error reporting. On theother hand, when the result of comparing the prior map with the scandata is within the error range, the prior map may be corrected based onthe scan data.

The scan condition setting unit 260 may use a prior map corrected in themap generating unit 250 as a reference map, and may set a scan conditionregarding the movable marking apparatus 20 by taking into account dataincluded in the reference map.

While the position detecting unit 270 converts data and compares theconverted data with the scan data, an error may occur. For example, aposition of the movable marking apparatus 20 determined in the positiondetecting unit 270 may momentarily dramatically change, or a position ofthe movable marking apparatus 20 may discontinuously change.

To address such a problem, the position correcting unit 280 may correcta position of the movable marking apparatus 20 by comparing a positionof the movable marking apparatus 20 detected in the position detectingunit 270 with a movement path set in the scan condition setting unit260.

In an embodiment, the position correcting unit 280 may correct aposition of the movable marking apparatus 20 by using an IMU (an inertiasensor) included in the sensing unit 230. The IMU may provideacceleration sensing data and geomagnetic field sensing data, and theposition detecting unit 270 may correct an error occurring during aprocess of comparing the reference map data with the scan data by usingthe acceleration sensing data and the geomagnetic field sensing data.

An apparatus for correcting the reference map data and the scan data isnot limited to the IMU, and any sensor and/or measuring instrumentcapable of correcting a position of the movable marking apparatus may beused.

The scan condition setting unit 260 may set a movement path of themovable marking apparatus 20 in response to the marking data, may set ascan position within the space targeted for scanning by taking intoaccount reference map data corresponding to the space targeted forscanning, and may set a scan angle of the sensing unit corresponding tothe scan position. For example, the scan condition setting unit 260 mayset the scan position and/or the scan angle by taking into accountcharacteristics of an object in space targeted for scanning obtainedfrom reference map data corresponding to the space targeted forscanning.

The movement path may include a pattern or a line according to themarking data. In an embodiment, the movable marking apparatus 20 may beused to make a particular mark on a position desired by a worker withinparticular space, and the movable marking apparatus 20 may move alongthe movement path and make a mark or draw a line on the working surfaceby using the marking unit 240 at a position included in the markingdata.

In another embodiment of the disclosure, the sensing unit 230 mayfurther include an imaging unit (not shown) and/or an image signalgenerator (not shown). The imaging unit may include a camera unit suchas a charge-coupled device (CCD) camera and may capture an image of theworking surface by using the camera unit.

The image signal generator is electrically connected to the imaging unitand generates an image signal based on the image captured in the imagingunit. The position detecting unit 270 may calculate and/or check aposition of the movable marking apparatus 20 on the marking data basedon the image signal.

The imaging unit may capture an image of a result of work performed inresponse to the marking data, and the image signal is data correspondingto the data and may be compared with the marking data. Accordingly, theposition detecting unit 270 may determine a position of the movablemarking apparatus 20 by comparing the image signal with the marking dataand may determine whether or not the marking unit 240 performs workdesired by a worker in response to the marking data. In addition, theposition detecting unit 270 may provide a result obtained through theimaging unit to the worker and may provide current work status throughthe image signal or in another format of data.

That is, a work result corresponding to the marking data may be providedto the worker in a format of an image signal obtained through theimaging unit or may be provided to the worker in a format of dataobtained through a sensor capable of recognizing the work result (forexample, position data corresponding to the work data, data including aresult of comparing the work result with the marking data, etc.).

Through the above configuration, even when the worker is located inspace separate from the movable marking apparatus 20, the worker maycheck a marking operation performed through the movable markingapparatus 20 in real time.

In addition, the position detecting unit 270 may take into accountrelative positions of the movable marking apparatus 20 and the markingunit 240. For example, positions of the movable marking apparatus 20 andthe marking unit 240 may be respectively defined as a first position anda second position, and in an idle state in which the movable markingapparatus 20 does not operate, the first position and the secondposition may be defined as matching.

The marking unit 240 may move independently from the movable markingapparatus 20, and when the movable marking apparatus 20 operates, thesecond position and the first position may not match.

The marking unit 240 may move independently from the movable markingapparatus 20, and may freely move in various directions including up anddown and left and right. Accordingly, through an operation in which amark is made on a current position as the marking unit 240 verticallydescends in a state in which the movable marking apparatus 20 does notmove, the current position may be set as a reference point.

Alternatively, when the movable marking apparatus 20 moves in a state inwhich the marking unit 240 is fixed, a position of the marking unit 240may subordinately change in response to a position of the movablemarking apparatus 20, and in this regard, the movable marking apparatus20 may move along a movement path corresponding to the marking data.

Alternatively, the marking unit 240 may move independently from amovement direction of the movable marking apparatus 20. As an example,the movable marking apparatus 20 may move along a predetermined movementpath, and at the same time, the marking unit 240 may perform markingwork corresponding to the marking data independent from the movementpath. In another embodiment, the marking unit 240 may perform markingwork in response to the marking data in a state in which the movablemarking apparatus 20 does not move.

A sub sensor (not shown) for determining a position of the marking unit240 operating independently of the movable marking apparatus 20 may beincluded. The sub sensor may be included in the sensing unit 230, andthe position detecting unit 270 may determine a position of the markingunit 240 (the second position) by using data measured through the subsensor and thus may calculate a distance between the movable markingapparatus 20 and the marking unit 240.

According to another embodiment of the disclosure, as described above,the movable marking apparatus 20 and the marking unit 240 may moveindependently of each other and thus may operate properly in response toa work situation.

The position detecting unit 270 may calculate the first position, whichis a position of the movable marking apparatus 20, by using the secondposition and a distance between the movable marking apparatus 20 and themarking unit 240, or correspondingly, may calculate the second position,which is a position of the marking unit 240, by using the first positionand a distance between the movable marking apparatus 20 and the markingunit 240.

Since the second position refers to a position of the marking unit 240,the position detecting unit 270 may determine the second position bycomparing the marking data with the image signal reflecting a result ofwork performed by the marking unit 240.

Accordingly, even though a position of the movable marking apparatus 20determined through a result of comparing the map data with the scan datais not accurate, accuracy of position determination of the movablemarking apparatus 20 may be improved by using the second position.

In addition, the position detecting unit 270 may include an alarm module(not shown) for outputting an alarm when a position of the movablemarking apparatus 20 and the movement path turn out to be a mismatch asa result of comparison. Through the alarm, a worker may recognize thatthe position of the movable marking apparatus 20 is off a preplannedposition, and may control a subsequent operation of the movable markingapparatus 20.

When a position of the movable marking apparatus 20 determined by usingthe IMU or a position of the marking unit 240 (the second position) isoff the movement path by a predetermined range or more, the positioncorrecting unit 280 may correct the position of the movable markingapparatus 20 so as to correspond to the movement path. In this regard,the position correcting unit 280 may control the position of the movablemarking apparatus 20 by controlling the driving unit 220.

That is, the position correcting unit 280 may determine whether tocorrect a position of the movable marking apparatus 20 according to adegree of mismatch between the position of the movable marking apparatus20 and the movement path. In addition, whether to correct a position ofthe movable marking apparatus 20 may be determined by a worker checkingthe alarm.

As described above with reference to FIG. 4, the sensing unit 230 mayfurther include an encoder, and the position correcting unit 280 maycorrect a position of the movable marking apparatus 20 by usingdisplacement data of the movable marking apparatus 20 provided from theencoder.

In an embodiment, an image of a work result regarding the workingsurface may be obtained by using the imaging unit (not shown) and theimage signal generator (not shown) and may be compared with the markingdata input to the data receiving unit 210. Alternatively, instead ofobtaining the work result as an image, the work result may be obtainedin another form by using a photosensitizer, light waves, etc.

When the work result turns out to have an error as a result of comparingthe work result with the marking data, the marking unit 240 may performmarking work again by deleting a wrongly marked portion at a point wherethe corresponding error occurs or by painting over the wrongly markedportion.

Alternatively, a result of comparing the work result with the markingdata may be provided to a user, and thus, the user may be allowed todetermine whether to perform marking work again.

In another embodiment of the disclosure, the scan condition setting unit260 may allow the sensing unit 230 to perform second scanning on thespace targeted for scanning before the movable marking apparatus 20starts marking work.

For example, when the reference map is generated by using the scanningsensor, a worker of the space targeted for scanning may be recognized asan object, and while the movable marking apparatus 20 performs work, theworker may not be in the space targeted for scanning.

In this regard, the reference map may be updated by using scan dataobtained through the second scanning, and thus, marking work may beperformed after unnecessary data is removed.

Alternatively, an imaging apparatus may be provided in the sensing unit230 and may be set to suspend, when a moving object is detected during ascanning operation for generating reference map data, a scanningoperation and resume the scanning operation after a certain time.

FIG. 10 is a drawing schematically illustrating configurations of amovable marking system 300 according to another embodiment.

Referring to FIG. 10, the movable marking system 300 includes a movablemarking apparatus 30 and a computing apparatus 31, and the movablemarking apparatus 30 may include a data receiving unit 310, a drivingunit 320, and a sensing unit 330. The computing apparatus 31 may includea map generating unit 340, a scan condition setting unit 350, and aposition detecting unit 360, and the movable marking apparatus 30 mayfurther include a control unit 370.

The data receiving unit 310, the driving unit 320, the sensing unit 330,the map generating unit 340, the scan condition setting unit 350, andthe position detecting unit 360 perform substantially the same functionsas the data receiving unit 210, the driving unit 220, the sensing unit230, the map generating unit 250, the scan condition setting unit 260,and the position detecting unit 270 described above with reference toFIG. 9, and thus, a repeated description thereof is omitted below.

Although the map generating unit 340, the scan condition setting unit350, and the position detecting unit 360 are illustrated as beingincluded in the separate computing apparatus 31, this is merely anembodiment, and the disclosure is not limited thereto. Accordingly, asdescribed above with reference to FIG. 1, the computing apparatus 31 maybe coupled to the movable marking apparatus 30, and in this regard, themap generating unit 340, the scan condition setting unit 350, and theposition detecting unit 360 may serve as components of the movablemarking apparatus 30.

The control unit 370 may control a position of the movable markingapparatus 30, and when a position of the movable marking apparatus 30detected by the position detecting unit 360 is off a preset movementpath by a predetermined range or more, may adjust the position of themovable marking apparatus 30 in response to the movement path.

When the movable marking system 300 illustrated in FIG. 10 includes thesame configurations as a marking unit described above with reference toFIG. 9, the control unit 370 may control a position of the marking unit,and when a position of the movable marking apparatus 30 is off themovement path by less than the predetermined range, the position of themarking unit may be adjusted in response to the movement path.

The marking unit may freely move up and down and left and rightindependently of the movable marking apparatus 30. Accordingly, when themovable marking apparatus 30 is slightly off the movement path, aposition of the marking unit may be adjusted without moving the movablemarking apparatus 30, and thus, marking work may be performed on aposition corresponding to marking data present on the movement path.

The movable marking apparatus 30 may include a plurality of markingunits, and the plurality of marking units may be separated from themovable marking apparatus 30 to simultaneously perform marking work atdifferent positions.

When the control unit 370 performs an operation of adjusting a positionof the movable marking apparatus 30, the control unit 370 may beunderstood as performing substantially the same function as the positioncorrecting unit 280 described above with reference to FIG. 9.Accordingly, when a position of the movable marking apparatus 30determined by using an IMU or a position of the marking unit (the secondposition) described above with reference to FIG. 9 is off the movementpath by a predetermined range or more, the control unit 370 may correctthe position of the movable marking apparatus 30 so as to correspond tothe movement path.

In this regard, the control unit 370 may control a position of themovable marking apparatus 30 by controlling a driving apparatus (notshown) providing power to the movable marking apparatus 30.

FIG. 11 is a drawing illustrating an example of an operation in which amovable marking system corrects a position on space.

As described above with reference to the preceding drawings, the scancondition setting unit 140, 260, or 350 may set a movement path of amovable marking apparatus in response to marking data, may set a scanposition within space targeted for scanning by taking into accountreference map data corresponding to the space targeted for scanning, andmay set a scan angle of the sensing unit 130, 230, or 330 correspondingto the scan position.

In FIG. 11, a dash line denotes the movement path set by the scancondition setting unit 140, 260, or 350, and a solid line denotes anactual movement path of the movable marking apparatus.

Movement paths illustrated in FIG. 11 are used as an example fordescription of the disclosure, and the disclosure is not limited to themovement paths.

As described above with reference to FIGS. 9 and 10, the positioncorrecting unit 280 and the control unit 370 may compare a position ofthe movable marking apparatus detected by the position detecting unit270 or 360 with a movement path set by the scan condition setting unit260 or 350 and thus may correct the position of the movable markingapparatus.

In this regard, when a position of the movable marking apparatus is offa preset movement path by a certain range or more, the positioncorrecting unit 280 and the control unit 370 may adjust the position ofthe movable marking apparatus such that the position of the movablemarking apparatus corresponds to the preset movement path.

In FIG. 11, a first correction point Z1 and a second correction point Z2denote points where a position of the movable marking apparatus is off apreset movement path by the certain range or more. The positiondetecting unit 270 or 360 may detect a position of the movable markingapparatus continuously, and the position correcting unit 280 and thecontrol unit 370 may compare the detected position with a presetmovement path of the movable marking apparatus.

At the first correction point Z1 and the second correction point Z2, theposition of the movable marking apparatus may be determined as being offthe preset movement path by a certain range or more, and thus, inresponse, the position correcting unit 280 and the control unit 370 mayadjust the movable marking apparatus so as to approach the presetmovement path.

An error range for correcting a position of the movable markingapparatus may be set as small as possible to allow the movable markingapparatus to perform an accurate marking operation in response tomarking data, and in addition, it is important to improve accuracy ofposition determination of the movable marking apparatus.

A movable marking system according to the disclosure may use anauxiliary apparatus such as an IMU or may use a position of a markingunit included in the movable marking apparatus to accurately detect aposition of the movable marking apparatus and thus adjust or correct theposition of the movable marking apparatus. Alternatively, as describedabove, a transmitter, which is installed at an arbitrary position, and areceiver, which may be disposed in the movable marking apparatus, may beused.

FIG. 12 is a drawing schematically illustrating configurations of themarking unit 240 according to an embodiment.

Referring to FIG. 12, the marking unit 240 according to an embodiment ofthe disclosure may include a first marking module 241 and a secondmarking module 242. As described above with reference to FIG. 9, themarking unit 240 may perform a marking operation on a working surface inresponse to marking data, and the marking data may include design dataand text data.

The first marking module 241 performs a marking operation correspondingto the design data, and the second marking module 242 performs a markingoperation corresponding to the text data. The first marking module 241and the second marking module 242 are driven independently of eachother, and to this end, the first marking module 241 and the secondmarking module 242 may respectively include separate driving modules(not shown).

As described above with reference to FIG. 9, any tool, such as ink, aphotosensitizer, light, or sound waves, capable of performing a markingoperation on a working surface may be used as the marking unit 240, anda tool for performing marking by applying physical pressure may also beused. Such marking tools may be understood as being applied to the firstmarking module 241 and the second marking module 242.

FIG. 13 is a drawing schematically illustrating configurations of amarking module according to another embodiment.

As described above with reference to FIG. 12, the marking unit 240 mayinclude the first marking module 241 and the second marking module 242,and thus, the first marking module 241 and the second marking module 242may perform a marking operation corresponding to design data and amarking operation corresponding to text data, respectively. FIG. 13illustrates an example of configurations of the first marking module241, and configurations of the second marking module 242 may besubstantially the same as the configurations illustrated in FIG. 13.

Referring to FIG. 13, the first marking module 241 may include an inksupplier 241 c, a first nozzle unit 241 a, and a second nozzle unit 241b. The first nozzle unit 241 a performs marking in a first direction,and the second nozzle unit 241 b performs marking in a second directiondifferent from the first direction.

The first marking module 241 may further include a third nozzle unit(not shown) and a fourth nozzle unit (not shown) in addition to thefirst and second nozzle units 241 a and 241 b, and the third and fourthnozzle units may perform marking in directions different from the firstand second directions, respectively. Accordingly, the first markingmodule 241 may perform marking work in various directions by using aplurality of sub nozzle units.

In an embodiment of the disclosure, the plurality of sub nozzle unitsmay be arranged in a row, and a distance between the plurality of subnozzle units may not be fixed and may flexibly change according to awork environment of the movable marking apparatus 10 or 20 orcharacteristics of the marking data.

The first marking module 241 may perform marking work by selecting someof the plurality of sub nozzle units required for the work, or mayperform marking work by adjusting a distance between the plurality ofsub nozzle units.

Although, in FIG. 13, the first direction and the second direction maydenote an x-axis direction and a y-axis direction, respectively, thefirst and second directions are not limited thereto. The first nozzleunit 241 a and the second nozzle unit 241 b may be connected to the inksupplier 241 c and may each include one or more nozzles.

The first marking module 241 is not limited to injecting a liquidpigment such as ink and may inject a pigment of a solid or gel type. Thefirst marking module 241 may use a unit of a pen or brush type todirectly apply a pigment of an emulsion or gel type such as ink or pasteon a working surface or directly apply a pigment of a solid type on aworking surface.

In addition, the first marking module 241 may be provided to performmarking on a working surface by applying a physical change to theworking surface. For example, the first marking module 241 may beprovided to perform marking by applying pressure, such as a scratch, toa surface of the working surface.

It will be apparent to one of ordinary skill in the art thatconfigurations and operations of the first marking module 241 describedabove may be applied in the same way to the second marking module 242described above with reference to FIG. 12.

In another embodiment of the disclosure, the marking unit 240 mayperform simulated marking work before performing actual marking work. Inthis regard, the marking unit 240 may control only a position of anozzle in response to marking data without performing actual markingwork.

The sensing unit 230 may further include a nozzle position sensor (notshown) for calculating a position of the nozzle, and the nozzle positionsensor may generate data regarding a position of the nozzle during thesimulated marking work.

The marking unit 240 may compare the marking data with the dataregarding a position of the nozzle and thus may predict whether aproblem will occur during a process of performing actual marking work.For example, the marking unit 240 may perform simulated marking workagain at a position where the marking data and the data regarding aposition of the nozzle do not match.

When a position of the nozzle does not correspond to the marking dataeven after simulated marking work is performed a preset number of timesor more, the marking unit 240 may output an error alarm. In response tothe alarm, a user may determine whether to perform actual marking workby comparing data regarding a position of the nozzle with the markingdata. Alternatively, through the alarm, the marking unit 240 may allowthe user to figure out a problem that occurred at the position where thetwo pieces of data do not match.

For example, when a working surface is uneven, for example, caves in, atthe position where the two pieces of data do not match, preparatory workmay be required to perform marking work on the corresponding workingsurface, and thus, when a mismatch of data occurs, marking work may beperformed smoothly by outputting an alarm to a user.

As a mismatch occurs between the marking data and the data regarding aposition of the nozzle, simulated marking work may be performed again.Accordingly, when data regarding a position of the nozzle newly obtainedwithin the preset number of times matches the marking data, the markingunit 240 may determine a temporary problem as having occurred and mayperform actual marking work.

FIG. 14 an example of a plan view of a movable marking apparatus,according to an embodiment.

Referring to FIG. 14, the movable marking apparatus may move by using apair of wheels arranged on both sides thereof and may include a scanningsensor. Although not illustrated in FIG. 14, the movable markingapparatus may further include at least one wheel at a lower portionthereof and thus may maintain balance. However, the movable markingapparatus is not limited to configurations illustrated in FIG. 14, forexample, the pair of wheels, and may include any configuration providingpower to the movable marking apparatus to move to an arbitrary position.

For example, the movable marking apparatus may be configured to becapable of flying like a drone and may be configured through a pluralityof pairs of driving apparatuses.

As described above with reference to FIG. 1, a position of the movablemarking apparatus may be determined through the scanning sensor, andthus, the position of the movable marking apparatus may be understood asbeing substantially the same as a position of the scanning sensor.

In addition, the position of the movable marking apparatus, that is, theposition of the scanning sensor, may be denoted by coordinates of(p_(x), p_(y)), and the scanning sensor may rotate due to a motor. Inaddition, a rotation direction of the scanning sensor may be variouslycontrolled as necessary. In this regard, an angle of the scanning sensormay be denoted based on an x-axis of FIG. 14, and a position of anobject detected by the scanning sensor may be denoted by polarcoordinates of (θ_(L), d). In this regard, d denotes a distance to thedetected object.

The movable marking apparatus includes a marking unit (not shown) in aposition corresponding to the scanning sensor at a lower portionthereof. The marking unit may freely move up and down and left and rightto perform work corresponding to marking data and may perform anoperation of making a certain mark at a specific position of a workingsurface or drawing a line on a movement path in response to the markingdata.

FIG. 15 is a drawing illustrating an example of a movement path of amovable marking apparatus, according to an embodiment.

The movement path of the movable marking apparatus includes informationregarding a plurality of scan positions and a scan angle of a scanningsensor. Referring to FIG. 15, the movable marking apparatus performs ascanning operation by using the scanning sensor at a first point (x1,y1, θ1) to a seventh point (x7, y7, θ7).

FIG. 15 illustrates several specific scan positions where the movablemarking apparatus performs a scanning operation, and this is intended toaccurately identify a position of the movable marking apparatus.

However, a movable marking apparatus according to another embodiment ofthe disclosure may continuously perform a scanning operation whilemoving along the movement path set without designating a specific scanposition.

The scan angle refers to a scanning angle of the scanning sensor at eachscan position and may be represented as degrees or radians. A size ofthe scan angle may be represented based on an x-axis or may berepresented based on an angle of the scanning sensor corresponding to atime when a scanning operation at the very previous scan position isfinished.

The movable marking apparatus stops at each scan position, and while themovable marking apparatus stops at the scan position, the movablemarking apparatus scans surrounding space by rotating the scanningsensor. However, as described above, the movable marking apparatus maycontinuously perform a scanning operation while moving along themovement path set without designating a specific scan position.Accordingly, this may be understood as not performing a stop operationat the scan position.

In addition, whether or not a position of the movable marking apparatusmatches the movement path may be determined by comparing scan dataobtained through the scanning operation with the reference map data.

Accordingly, through a movable marking system according to anembodiment, the movable marking apparatus may perform an operation ofmarking a specific mark or drawing a line at a corresponding positionaccording to marking data while moving along a set movement path.

At the same time, whether or not a position of the movable markingapparatus matches the movement path, which is previously set, may bedetermined through a scanning operation performed via the scanningsensor at a plurality of scan positions, and when the position of themovable marking apparatus does not match the movement path, the positionmay be controlled to move along the movement path.

Although FIG. 15 illustrates a total of 7 scan positions, the disclosureis not limited thereto, and the scan position may be variously changedaccording to positions of a pillar, a window, an obstacle, etc. in thespace targeted for scanning. When there is empty space in the spacetargeted for scanning, a scan signal may not be reflected in the emptyspace, and thus, the plurality of scan positions and the scan angle maybe set by taking a position of the empty space into account.

FIG. 16 is a drawing illustrating an example of a reference map obtainedthrough a movable marking apparatus, according to another embodiment.

FIG. 16 illustrates a reference map obtained through scan data obtainedthrough a scanning sensor at a reference position, and it may be foundthat reflection of a scan signal does not occur at a position whereglass exists and thus normal scan data is not obtained starting from aposition of the glass to the reference position.

It may also be found that scan data is not normally obtained startingfrom space behind a pillar. Accordingly, generation of the reference mapusing the scan data obtained through the scanning sensor allowsapproximate determination of a position where the glass exists and aposition where the pillar or an obstacle exists within space targetedfor scanning.

When the reference map is generated by using scan data obtained byrotating a scanning sensor that is in a stop state, a scan distanceincreases according to a size of space targeted for scanning, and thus,accuracy may decrease. Accordingly, the reference map may be used asreference data to set a movement path, a scan position, and a scan angleof the movable marking apparatus.

When there is a drawing for the space targeted for scanning, using thedrawing and the reference map together may be useful in implementing anaccurate operation of the movable marking apparatus.

A movement path, a scan position and/or a scan angle of the movablemarking apparatus may be set to obtain accurate scan data regarding thespace targeted for scanning, and in FIG. 9, a position and an angleseparate as far as possible from the glass and the pillar, including thereference position, may be set.

FIG. 17 is a flowchart schematically illustrating a flow of a method ofcontrolling a movable marking apparatus, according to an embodiment.

Referring to FIG. 17, a method of controlling a movable markingapparatus, according to an embodiment, may include an informationreceiving operation (S110), a movement path setting operation (S120), ascan position and scan angle setting operation (S130), a markingapparatus position determining operation (S140), and a marking apparatusposition correcting operation (S150).

A movable marking apparatus capable of being controlled according to amethod of controlling a movable marking apparatus may move through adriving apparatus (not shown) providing power and may include a scanningsensor. The driving apparatus may be in any form that provides power tothe movable marking apparatus and thus allows the movable markingapparatus to move to an arbitrary position. For example, the movablemarking apparatus may be configured to be capable of flying like a droneor may be configured through a plurality of pairs of drivingapparatuses. The previous embodiments may all be applied to detailedconfigurations of the movable marking apparatus.

In the information receiving operation (S110), information regardingspace targeted for scanning is received.

In the information receiving operation (S110), marking data regarding aworking surface included in the space targeted for scanning may bereceived. The marking data refers to data that allows the movablemarking apparatus to mark or draw a specific pattern on the workingsurface, and the movable marking apparatus may perform an operation ofmaking a mark corresponding to the marking data or drawing a line on theworking surface by using a separate marking unit (not shown).

In the movement path setting operation (S120), a movement path of themovable marking apparatus is set. Although the movement path may bedetermined by taking into account operation characteristics of themovable marking apparatus, in an embodiment, the movement path mayinclude a pattern or a line according to the marking data. In anembodiment, the movable marking apparatus may be used to make a specificmark on a position desired by a worker within specific space, and themovable marking apparatus may move along the movement path and make amark or draw a line on the working surface by using the marking unit ata position included in the marking data.

In the scan position and scan angle setting operation (S130), aplurality of scan positions within the space targeted for scanning and ascan angle of the scanning sensor at each of the plurality of scanpositions may be set by taking reference map data into account. Indetail, a scan position and/or a scan angle may be set by taking intoaccount characteristics of an object in the space targeted for scanningobtained from reference map data corresponding to the space targeted forscanning.

The reference map may be understood as a map indicating a shape of thespace targeted for scanning, and in an embodiment, the reference map maybe a plan view corresponding to the space targeted for scanning.

The scan position and scan angle setting operation (S130) is anoperation of setting a scan condition of the scanning sensor within thespace targeted for scanning. When the movement path of the movablemarking apparatus is set in the movement path setting operation (S120),an arbitrary point on the movement path is designated and the designatedpoint is set as a scan position in the scan position and scan anglesetting operation (S130). In response, when the movable markingapparatus reaches the scan position, the scanning sensor performs ascanning operation. In this regard, the scanning sensor rotatesaccording to a scan angle set in the scan position and scan anglesetting operation (S130).

A scan position and a scan angle are set by taking the reference mapdata into account, and for example, a position and an angle where apillar, a window, an obstacle, etc. in the space targeted for scanningmay be avoided may be set as the scan position and the scan angle. Inaddition, when there is empty space within the space targeted forscanning, a scan signal may not be reflected in the empty space, andthus, the plurality of scan positions and the scan angle may be set bytaking into account a position of the empty space.

In the marking apparatus position determining operation (S140), aposition of the movable marking apparatus is determined by comparingscan data obtained through the scanning sensor at the scan position withthe reference map data.

The reference map data may be represented as coordinates of pixelsincluded in an image frame, and coordinates of a pixel corresponding toa position where an object exists may have a different value fromcoordinates of a pixel corresponding to an empty position. As describedabove, data obtained through the scanning sensor may be obtained in theform of polar coordinates, and when the reference map data is comparedwith the scan data, a position of the movable marking apparatus in thespace targeted for scanning may be determined.

The reference map data and the scan data are not limited to dataregarding coordinates of pixels and data in the form of polarcoordinates, respectively. The reference map data may also include datain a format of a vector, a polar coordinate, etc., and the scan data mayalso include data in a grid format.

In more detail, in the marking apparatus position determining operation(S140), the reference map data may be converted into data in the form ofpolar coordinates, which is obtained through the scanning sensor, andthe converted data may be compared with the scan data.

In the marking apparatus position determining operation (S140), aposition of the movable marking apparatus may be accurately determinedby using an IMU sensor. The IMU may provide acceleration sensing dataand geomagnetic sensing data, and in the marking apparatus positiondetermining operation (S140), an error that occurred during a process ofcomparing the reference map data with the scan data may be corrected byusing the acceleration sensing data and the geomagnetic sensing data.

An apparatus for correcting the reference map data and the scan data isnot limited to the IMU, and any sensor and/or measuring instrumentcapable of correcting a position of the movable marking apparatus may beused. For example, an encoder capable of providing displacement data ofthe movable marking apparatus may be used.

In the marking apparatus position determining operation (S140), aposition signal output from a transceiver installed at an arbitraryposition may be received and/or a position of a marker installed at anarbitrary position may be sensed, and a position of the movable markingapparatus may be determined from the position signal.

An operation performed in the marking apparatus position determiningoperation (S140) is intended to determine a position of the movablemarking apparatus as accurately as possible. The previous embodimentsmay all be applied to concrete embodiments of the transceiver and/or themarker.

FIG. 18 is a flowchart schematically illustrating a flow of a method ofcontrolling a movable marking apparatus, according to anotherembodiment.

Referring to FIG. 18, the method of controlling a movable markingapparatus may include an information receiving operation (S210), amovement path setting operation (S220), a scan data obtaining operation(S230), a reference map generating operation (S240), a scan position andscan angle setting operation (S250), a marking apparatus positiondetermining operation (S260), and a marking apparatus positioncorrecting operation (S270).

In the information receiving operation (S210), the movement path settingoperation (S220), the scan position and scan angle setting operation(S250), the marking apparatus position determining operation (S260), andthe marking apparatus position correcting operation (S270), operationssubstantially the same as those performed in the information receivingoperation (S110), the movement path setting operation (S120), the scanposition and scan angle setting operation (S130), and the markingapparatus position determining operation (S140) described above withreference to FIG. 17 may be performed, and thus, a repeated descriptionthereof is omitted below.

In the scan data obtaining operation (S230), a scanning sensor of themovable marking apparatus is rotated at a reference position withinspace targeted for scanning, and thus, scan data of the space targetedfor scanning is obtained.

The reference position may be an arbitrary position within the spacetargeted for scanning, and in general, a center point of the spacetargeted for scanning may be selected as the reference position.However, the reference position is not limited to the position withinthe space targeted for scanning, and in some cases, the outside of thespace targeted for scanning may be selected as the reference position.

A position close to a window or a position where there is an adjacentobstacle may not be suitable for the reference position. At the window,the probability that a scan signal output from the scanning sensor isnot reflected is high, and thus, there may be a problem with obtainingthe scan data. When there is an obstacle nearby, it may be difficult toobtain scan data of space behind the obstacle.

In addition, in a space where there is no object reflecting a scansignal output from the scanning sensor, it may be difficult to obtainscan data, and thus, the reference position may be arranged in an emptyspace within the space targeted for scanning to set a position where apillar, an obstacle, or the like may be scanned as the referenceposition.

In a state where the movable marking apparatus stops at the referenceposition, the scanning sensor scans the space targeted for scanning byrotating 360 degrees and thus generates the scan data. If necessary, ascan angle of the scanning sensor may be controlled in a heightdirection through tilt control, etc.

In the reference map generating operation (S240), a reference mapregarding the space targeted for scanning is generated from the scandata. In the scan position and scan angle setting operation (S250), ascan condition of the movable marking apparatus may be set by takinginto account the reference map generated in the reference map generatingoperation (S240).

In an embodiment of the disclosure, in the reference map generatingoperation (S240), the reference map may be generated by applying a SLAMalgorithm to the scan data.

The reference map may include image data of pixels included in an imageframe corresponding to the scan data. For example, when the spacetargeted for scanning is represented as one frame, a pixel correspondingto a position where an object exists may be displayed as black, and aposition corresponding to empty space may be displayed as white.

However, this is merely an embodiment of a data format that thereference map data may include, the disclosure is not limited toincluding color information regarding an individual pixel, and thereference map data may be represented in a format such as a vector, apolar coordinate, etc.

In another embodiment, the scan data obtaining operation (S230) may beomitted, and an operation of receiving a drawing corresponding to thespace targeted for scanning may be further included.

The drawing includes information regarding the space targeted forscanning, and when the drawing exists, the drawing may play the samerole as the reference map, and in the scan position and scan anglesetting operation (S250), a plurality of scan positions and a scan angleof the scanning sensor at each of the plurality of scan positions may beset by taking the drawing into account.

When the drawing exists, a process of generating the reference map fromscan data may be unnecessary, however, the drawing and the reference mapmay be used together. For example, when accuracy of the drawing is notsufficiently reliable, the reference map generated by using the scandata and the drawing may be selectively and/or simultaneously used.

Accordingly, in the scan position and scan angle setting operation(S250), a scan position of the movable marking apparatus and a scanangle at the scan position may be set by taking into account thereference map and the drawing together.

In addition, in the marking apparatus position determining operation(S260), a position of the movable marking apparatus may be determined bycomparing scan data obtained at the scan position, the reference map,and the drawing.

In the marking apparatus position correcting operation (S270), aposition of the movable marking apparatus is compared with the movementpath, and the position of the movable marking apparatus is corrected.

In the marking apparatus position determining operation (S260), data maybe converted, and an error may occur during a process of comparing theconverted data with the scan data. For example, a position of themovable marking apparatus determined in the marking apparatus positiondetermining operation (S260) may momentarily dramatically change, or aposition of the movable marking apparatus may discontinuously change. Inthis case, the movable marking apparatus may be off the movement path.

In the marking apparatus position correcting operation (S270), when aposition of the movable marking apparatus determined in the markingapparatus position determining operation (S260) is off the movement pathby a predetermined range or more, the position of the movable markingapparatus may be corrected so as to correspond to the movement path.

FIG. 19 is a drawing schematically illustrating configurations of amovable marking system 400 according to another embodiment.

Referring to FIG. 19, the movable marking system 400 includes a datareceiving unit 410, a driving unit 420, a sensing unit 430, and aposition detecting unit 440.

The movable marking system 400 illustrated in FIG. 19 corresponds to themovable marking system 100 of FIG. 1 having the scan condition settingunit 140 excluded. That is, a configuration of setting a scan positionand a scan angle of a movable marking apparatus in space targeted forscanning may not be included.

In FIG. 19, the sensing unit 430 includes a scanning sensor forobtaining scan data while rotating 360 degrees without having a limitedangle range. When a scanning sensor capable of obtaining scan data onlywithin a limited angle range is used, an amount of scan data obtainedmay vary according to a direction that the scanning sensor faces, andthus, a process of setting a scan position and a scan angle at each scanposition is required to obtain a maximum amount of data.

On the other hand, when a scanning sensor is capable of rotating 360degrees, scan data corresponding to the space targeted for scanning maybe obtained at every position, and thus, the scan position and the scanangle may not be set. Accordingly, the movable marking system 400according to another embodiment may include only the data receiving unit410, the driving unit 420, the sensing unit 430, and the positiondetecting unit 440.

The sensing unit 430 may include a vertical driver (not shown) forcontrolling a scan height of the scanning sensor, and a height of thescanning sensor may be controlled according to a position of a movablemarking apparatus. Accordingly, even when a scan angle and a scanposition are not previously set by the scan condition setting unit 140described above with reference to FIG. 1, the height of the scanningsensor may be controlled.

The position detecting unit 440 may detect a position of the movablemarking apparatus by extracting some scan data from scan data obtainedthrough the sensing unit 430, and the extracted scan data may beunderstood as scan data for providing accurate information regarding thespace targeted for scanning.

The position detecting unit 440 may include a data extraction module(not shown) for extracting scan data required to detect a position ofthe movable marking apparatus.

The data extraction module may use the method described above withreference to FIG. 2 to extract scan data for providing more accurateinformation from scan data obtained through the sensing unit 430.

For example, a position and a scan angle range of a scanning sensorwhere more scan data may be obtained within the space targeted forscanning may be considered. Referring to FIG. 2 again, when the movablemarking apparatus moves from position A to position C via position B,scan data in a range of 135° to −45° may be extracted from scan dataobtained at position A.

Likewise, scan data in a range of 0° to 180° may be extracted from scandata obtained at position B, and scan data in a range of 45° to 225° maybe extracted from scan data obtained at position C.

The method described above is merely an embodiment that may be used toextract some scan data when a scanning sensor capable of rotating 360degrees is used, and the disclosure is not limited thereto. Accordingly,a process of extracting some scan data is not necessarily required, andit will be apparent to one of ordinary skill in the art that variousmethods may be used to extract some scan data.

Although not illustrated in FIG. 19, the movable marking system 400 mayinclude a tilt driver and/or a vertical driver capable of performingadjustment to allow the scanning sensor to perform scanning in anup-and-down direction.

FIG. 20 is a drawing schematically illustrating configurations of thesensing unit 430 according to another embodiment.

Referring to FIG. 20, the sensing unit 430 according to anotherembodiment includes a scanning sensor 431 and a fourth sensor 432. Thescanning sensor 431 performs the same operation as the scanning sensordescribed above with reference to the preceding drawings.

The fourth sensor 432 recognizes a reference position set on the spacetargeted for scanning. The reference position provides information fordetermining a position of the movable marking apparatus with respect tothe space targeted for scanning.

The movable marking system described above with reference to thepreceding drawings may determine a position of the movable markingapparatus from scan data obtained through a scanning sensor, and thereference position set on an arbitrary position of the space targetedfor scanning allows the position detecting unit 440 to detect a positionof the movable marking apparatus regardless of whether the scan data wasobtained or not.

An arbitrary position on a bottom floor, a wall surface, and/or aceiling of the space targeted for scanning may be set as the referenceposition, and an indicator that may be recognized with the fourth sensor432 and a communication apparatus may be installed at the referenceposition.

For example, the fourth sensor 432 may be a camera, and an image of anindicator marked on a bottom floor of the space targeted for scanningmay be captured through the camera, and the position detecting unit 440may analyze a form, a size, etc. of the captured image of the indicatorand detect a position where the image of the indicator was captured. Tothis end, the position detecting unit 440 may have stored therein animage of the indicator captured at the reference position. The positiondetecting unit 440 may compare the image of the indicator captured atthe reference position with an image of the indicator captured at anarbitrary position of the space targeted for scanning, and thus, whensizes and forms of the two images are identical, the position detectingunit 440 may determine the movable marking apparatus as being located atthe reference position.

As a movement distance of the movable marking apparatus performingvarious work including a scanning operation while moving in the spacetargeted for scanning increases, position determination errors mayincrease with accumulation, and a position of the movable markingapparatus may be corrected by allowing the fourth sensor 432 forrecognizing the reference position to recognize the reference positionperiodically or according to a user's request.

FIG. 21 is a drawing illustrating an example of a method of using areference position, according to another embodiment of the disclosure.

FIG. 21A illustrates an example of marking a reference position on abottom floor of the space S targeted for scanning. Referring to FIG.21A, reference position R may be marked on the bottom floor of the spaceS targeted for scanning, and the fourth sensor 432 described above withreference to FIG. 20 may recognize the reference position R.

Coordinates or a relative position of the reference position R withinthe space targeted for scanning may be stored in the position detectingunit 440, and while a movable marking apparatus performs work based onthe reference position R, the movable marking apparatus may be moved tothe reference position R periodically or according to the user'srequest.

At the reference position R, an image of an indicator marked on thereference position R may be captured through the fourth sensor 432, anda position of the movable marking apparatus may be detected by comparingthe captured image with an image of the indicator stored in the positiondetecting unit 440.

FIG. 21B illustrates an example of a plurality of reference positions inthe space S targeted for scanning. Referring to FIG. 21B, four pillarsare installed in the space S targeted for scanning, and each of thepillars constitutes a reference position within the space S targeted forscanning. A communication apparatus capable of communicating with thefourth sensor 432 may be installed at the pillar. The fourth sensor 432may calculate a distance to the pillar and may transmit informationregarding the calculated distance to the position detecting unit 440.

The position detecting unit 440 may detect a position of a movablemarking apparatus by using the information regarding the distance andposition information of the pillar with respect to the space S targetedfor scanning.

In the embodiment shown in FIGS. 21A and 21B, the movable markingapparatus may be controlled so as to be located at an arbitrary positionof the space S targeted for scanning (for example, a center of the spaceS targeted for scanning), and a position of the movable markingapparatus may be reset and then the movable marking apparatus may becontrolled to perform the next work.

The disclosure may be embodied as computer-readable code in acomputer-readable recording medium. The computer-readable recordingmedium may be any recording apparatus capable of storing data readableby a computer system. Examples of the computer-readable recording mediuminclude read-only memory (ROM), random-access memory (RAM), CD-ROM, amagnetic tape, a floppy disk, and an optical data storage device.

In addition, the computer-readable recording medium may be distributedover network-coupled computer systems so that the computer-readable codemay be stored and executed in a distributive manner. In addition,functional programs, code, and code segments for embodying thedisclosure may be easily inferred by programmers skilled in the art towhich the disclosure pertains.

The operations of all methods described herein may be performed in anysuitable order unless otherwise indicated herein or otherwise clearlycontradicted by the context. However the disclosure is not limited toany order of operations indicated above.

The use of any and all examples or exemplary language (e.g., “such as”)provided herein is intended merely to better illuminate the disclosureand does not pose a limitation on the scope of the disclosure unlessotherwise claimed. It will be understood by one of ordinary skill in theart that various modifications, adaptations, and changes may be madeaccording to design conditions and factors without departing from thescope of the appended claims and equivalents thereof.

Accordingly, the spirit of the disclosure should not be limited to theembodiments described above, and it will be understood that not only theappended claims but also all the scopes equivalent of the claims orequivalently changed therefrom are included in the spirit of thedisclosure.

INDUSTRIAL APPLICABILITY

A movable marking system capable of determining an environment of spacetargeted for scanning or space targeted for work and accuratelydetermining its position may be used.

1. A movable marking system comprising a movable marking apparatus, the movable marking system comprising: a data receiving unit for receiving information regarding space targeted for scanning; a driving unit for providing power to the movable marking apparatus; a sensing unit for scanning the space targeted for scanning; a scan condition setting unit for setting a movement path of the movable marking apparatus, setting a scan position for scanning the space targeted for scanning by taking into account reference map data corresponding to the space targeted for scanning, and setting a scan angle which is a scan direction of the sensing unit at the scan position; and a position detecting unit for detecting a position of the movable marking apparatus by comparing scan data obtained through the sensing unit at the scan position with the reference map data, wherein the reference map data is generated from a drawing corresponding to the space targeted for scanning.
 2. The movable marking system of claim 1, further comprising a map generating unit for generating the reference map data from scan data obtained through the sensing unit at a reference position.
 3. The movable marking system of claim 1, further comprising a position correcting unit for correcting the position of the movable marking apparatus by comparing the position of the movable marking apparatus detected in the position detecting unit with the movement path.
 4. The movable marking system of claim 3, wherein, when the position of the movable marking apparatus is off the movement path by a predetermined range or more, the position correcting unit corrects the position of the movable marking apparatus so as to correspond to the movement path.
 5. The movable marking system of claim 1, wherein the information regarding space targeted for scanning comprises marking data regarding the space targeted for scanning, wherein the movable marking system further comprises: a marking unit for performing a marking operation corresponding to the marking data; and a control unit for controlling the movable marking apparatus and a position of the marking unit, wherein, when the position of the movable marking apparatus detected in the position detecting unit is off the movement path by a predetermined range or more, the control unit adjusts the position of the movable marking apparatus in response to the movement path, and when the position of the movable marking apparatus is off the movement path by less than the predetermined range, the control unit adjusts the position of the marking unit in response to the movement path.
 6. The movable marking system of claim 5, wherein the movement path of the movable marking apparatus is set in response to the marking data.
 7. The movable marking system of claim 5, wherein the position detecting unit determines the position of the marking unit by comparing the marking data with data corresponding to an operation result of the marking unit, and the position detecting unit determines the position of the movable marking apparatus by taking into account a distance between the movable marking apparatus and the marking unit.
 8. The movable marking system of claim 1, wherein the scan position is on the movement path.
 9. The movable marking system of claim 1, wherein the position detecting unit receives a position signal from a transceiver in an arbitrary position and determines the position of the movable marking apparatus from the position signal.
 10. A method of controlling a movable marking apparatus comprising a rotatable scanning sensor and a driving apparatus, the method comprising: receiving information regarding space targeted for scanning; setting a movement path of the movable marking apparatus; setting a scan position for scanning the space targeted for scanning by taking into account reference map data corresponding to the space targeted for scanning, and setting a scan angle of the scanning sensor at the scan position; and determining a position of the movable marking apparatus by comparing scan data obtained through the scanning sensor at the scan position with the reference map data, wherein the reference map data is generated from a drawing corresponding to the space targeted for scanning.
 11. The method of claim 10, further comprising comparing the position of the movable marking apparatus with the movement path and correcting the position of the movable marking apparatus, wherein the correcting of the position of the movable marking apparatus comprises correcting, when the position of the movable marking apparatus determined in the determining of the position is off the movement path by a predetermined range or more, the position of the movable marking apparatus so as to correspond to the movement path.
 12. The method of claim 10, wherein the receiving of the information regarding the space targeted for scanning comprises receiving marking data regarding a working surface comprised in the space targeted for scanning, and the setting of the movement path comprises setting the movement path of the movable marking apparatus in response to the marking data.
 13. The method of claim 10, further comprising: obtaining scan data of the space targeted for scanning by rotating the scanning sensor at a reference position; and generating the reference map data of the space targeted for scanning from the scan data.
 14. The method of claim 10, wherein the scan position is on the movement path.
 15. A non-transitory computer-readable recording medium having recorded thereon a program for performing the method of claim
 10. 